An Omniscient Scheduling Oracle for Systems with Harmonic Periods
نویسندگان
چکیده
Most real-time scheduling problems are known to be NP-complete. To enable accurate comparison between the schedules of heuristic algorithms and the optimal schedule, we introduce an omniscient oracle. This oracle provides schedules for periodic task sets with harmonic periods and variable resource requirements. Three di erent job value functions are described and implemented. Each corresponds to a di erent system goal. The oracle is used to examine the performance of di erent on-line schedulers under varying loads, including overload. We have compared the oracle against Rate Monotonic Scheduling, Statistical Rate Monotonic Scheduling, and Slack Stealing Job Admission Control Scheduling. Consistently, the oracle provides an upper bound on performance for the metric under consideration.
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